HYPODERMIC SYRINGE ASSEMBLY

• US 3,556,099 A
• Filed: 05/27/1968
• Issued: 01/19/1971
• Est. Priority Date: 05/27/1968
• Status: Expired due to Term

• Current Assignee: Barbara A. Konopka, Francis J. Knight
• Original Assignee: Barbara A. Konopka, Francis J. Knight
• Inventors: Knight, Francis J., Konopka, Barbara A.
• Application Number:
  US04/732,410
• Time in Patent Office: 967 Days
• US Class Current: 604/232
• CPC Class Codes: A61M 2005/2407 from the rear
• CPC Class Codes: A61M 2005/247 with fixed or steady piercing means, e.g. piercing under movement of ampoule
• CPC Class Codes: A61M 2005/2492 via snap connection
• CPC Class Codes: A61M 5/24 Ampoule syringes, i.e. syringes with needle for use in combination with replaceable ampoules or carpules, e.g. automatic ampoules or carpules A61J1/06
• CPC Class Codes: A61M 5/349 using adhesive bond or glues

Abstract

A hypodermic syringe assembly comprising a disposable injection unit and a reusable plunger unit adapted to cooperate for dispensing medicament from an elongated cartridge positioned in the injection unit. The disposable injection unit comprises a hub structure, a double pointed needle extending through the hub, and elongated and resilient guides extending rearwardly of the hub to form a barrel for receiving the cartridge. The guides are radially flexible with respect to one another at the rear end of the barrel. The reusable plunger unit comprises a plug having means to simultaneously circumferentially engage the interior and exterior of the barrel at its rear end. The plug is adapted to fit inside the barrel and be locked in circumferential and axial engagement therewith. An elongated plunger is axially movable through said plug and has piston engaging means at its forward end and retracting means at its rear end. The plunger unit also includes flange means for cooperating with the plug to hold the rear ends of the guides in a fixed radial position when the plunger is locked in position in the barrel.

Claims

1. A hypodermic syringe assembly which comprises a disposable injection unit and a reusable plunger unit adapted to cooperate to dispense medicament from an elongated medicament-containing cartridge positioned in the injection unit;

said disposable injection unit comprising an elongated barrel closed at its front end and open at its rear end to provide a mouth for receiving said cartridge, said barrel comprising a hub structure at its front end for receiving a hypodermic needle and a plurality of angular spaced elongated and resilient guides extending rearwardly from the hub structure, said guides being radially flexible with respect to one another at the rear of said barrel, and a double pointed hollow needle mounted in said hub with its front end extending outwardly of the barrel and its rear end extending inwardly of the barrel;

said reusable plunger unit comprising a plug having means to simultaneously circumferentially engage the interior and exterior of said barrel at the mouth end and adapted to fit in the mouth of said barrel and be locked in circumferential and axial engagement therewith, and an elongated plunger passing longitudinally through said plug whereby an elongated medicament-containing cartridge having a piston at its rear end axially slideable therein may be inserted in said barrel through said mouth, said plug may be positioned in said mouth in radial and axial engagement therewith, and said plunger may be engaged with said piston for advancing and retracting the piston to aspirate and dispense medicament from the syringe.

2. A hypodermic syringe assembly according to claim 1, wherein said plug has a ridge portion and presents a generally cylindrical outer surface for insertion in the mouth of said barrel and at least one of said guides is circumferentially recessed to receive said ridge portion presentEd by the plug for locking said plug in position in the barrel, said guides defining an axially extending slot between them for cooperating with said ridge portion in inserting said plug in said barrel.

3. A hypodermic syringe assembly according to claim 2, wherein said means to engage the exterior of said barrel comprises flange means adapted to embrace the rear ends of said guides and prevent their further movement radially outwardly when said plug is locked in position in said barrel.

4. A hypodermic syringe assembly according to claim 3, wherein said flange means is in the form of an annular rim.

5. A hypodermic syringe assembly according to claim 3, wherein said flange means is integral with said plug.

6. A hypodermic syringe assembly according to claim 1, wherein said barrel and said plunger unit each present opposed finger grips adapted to cooperate with one another for operating the syringe when said plug is in position in said barrel.

7. A hypodermic syringe assembly according to claim 6 wherein said finger grips and said ridge portion are so located with respect to the recess in said barrel that the plug is locked in position in said barrel when the finger grips on said barrel are angularly aligned with the finger grips on said plunger unit.